Avoid using $(shell pwd) in Makefile, for better Windows compatibility.

CHANGES

+2015/10/12:
+Avoid using $(shell pwd) in Makefile, for better Windows compatibility.
+
 2015/10/05:
 Fixed a bug where inconsistent OCaml code was generated when --table
 and --external-tokens were used together. (Reported by Darin Morrison.)

src/Makefile

@@ -61,7 +61,11 @@ stage1:
 
 # Do not use . to refer to the current directory, because ocamlbuild
 # descends into another directory when executing commands.
-SRC   := $(shell pwd)
+# Do not use $(shell pwd) either, because this assumes we are running
+# on a Unix platform, and can fail on Windows.
+# So, use .., which works fine if ocamlbuild has effectively descended
+# into a subdirectory.
+SRC   := ..
 
 FLAGS := -v -lg 1 -la 1 -lc 1 --comment --infer --stdlib $(SRC) --strict --fixed-exception